Pinout for 964 Speedometer

[CBRacerX]

Greetings All Upgraders,

I am installing a 964 Speedo in my '87 911. I've got a way to connect the wiring from the '87 to the new speedo, but I don't know which pin is which on the 964 speedo (they are not marked, except perhaps 31b). I know this has been done before, does anyone have the key? There is a row of four pins, under which there is a single pin.

Thanks!!

Chris
'87 with 3.6 and non-functional speedo (bad combo!)

[CBRacerX]

So far I have been underwhelmed by the response to this question. I know it is Super Bowl Sunday, but surely someone has a clue on this. I'll try and post a pic to help jog memories.

Chris